She used
cans of black paint.
Step-by-step explanation:
Given,
Number of cans of black paint = x
Number of cans of white paint = y
Given equation;
y=2x Eqn 1
Amanda used 5 cans of white paint, therefore,
y=5
Putting in Eqn 1

Dividing both sides by 2

Writing in fraction form;

She used
cans of black paint.
Keywords: fraction, division
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